Induced fission modes of Fermium and Nobelium isotopes

The mass distributions of fragments resulting from the fission of the isotopes of Fm and No at excitation energies 0-50 MeV are studied with the statistical scission-point fission model. The available experimental mass distributions in the spontaneous and thermal-neutron-induced fission are well described and the origin of transition between asymmetric and symmetric fission modes with variations of neutron number and excitation energy is explored.